The Best Way to Wash Fruit and Vegetables

The Best Way to Wash Fruit and Vegetables.jpeg

How might we reduce our exposure to pesticide residues on fruits and vegetables? What about staying away from imported produce? Well, it turns out domestic produce may be even worse, dispelling the notion that imported fruits and vegetables pose greater potential health risks to consumers.

Buying organic dramatically reduces dietary exposure to pesticides, but it does not eliminate the potential risk. Pesticide residues are detectable in about one in ten organic crop samples, due to cross-contamination from neighboring fields, the continued presence of very persistent pesticides like DDT in the soil, and accidental or fraudulent use.

By choosing organic, one hopes to shift exposures from a range of uncertain risk to more of a range of negligible risk, but even if all we had to eat were the most pesticide-laden of conventional produce, there is a clear consensus in the scientific community that the health benefits from consuming fruits and vegetables outweigh any potential risks from pesticide residues. And we can easily reduce whatever risk there is by rinsing our fruits and vegetables under running water.

There are, however, a plethora of products alleged by advertisers to reduce fruit and produce pesticide residues more effectively than water and touted to concerned consumers. For example, Procter & Gamble introduced a fruit and vegetable wash. As part of the introduction, T.G.I. Friday's jumped on board bragging on their menus that the cheese and bacon puddles they call potato skins were first washed with the new product. After all, it was proclaimed proven to be 98% more effective than water in removing pesticides.

So researchers put it to the test and it did no better than plain tap water.

Shortly thereafter Procter & Gamble discontinued the product, but numerous others took its place claiming their vegetable washes are three, four, five or even ten times more effective than water, to which a researcher replied, "That's mathematically impossible." If water removes 50%, you can't take off ten times more than 50%. They actually found water removed up to 80% of pesticide residues like the fungicide, Captan, for example. So, for veggie washes to brag they are three, four, five, ten times better than water is indeed mathematically questionable.

Other fruit and vegetable washes have since been put to the test. Researchers compared FIT Fruit & Vegetable Wash, Organiclean, Vegi-Clean, and dishwashing soap to just rinsing in plain tap water. 196 samples of lettuce, strawberries, and tomatoes were tested, and researchers found little or no difference between just rinsing with tap water compared to any of the veggie washes (or the dish soap). They all just seemed like a waste of money. The researchers concluded that just the mechanical action of rubbing the produce under tap water seemed to do it, and that using detergents or fruit and vegetable washes do not enhance the removal of pesticide residues from produce above that of just rinsing with tap water alone.

That may not be saying much, though. Captan appears to be the exception. When plain water was tried against a half dozen other pesticides, less than half the residues were removed.

Fingernail polish works better, but the goal is to end up with a less toxic, not a more toxic tomato.

We need a straightforward, plausible, and safe method for enhanced pesticide removal. Is there anything we can add to the water to boost its pesticide-stripping abilities? Check out my video, How to Make Your Own Fruit & Vegetable Wash.

If you soak potatoes in water, between about 2% to 13% of the pesticides are removed, but a 5% acetic acid solution removes up to 100%. What's that? Plain white vinegar. But 5% is full strength.

What about diluted vinegar? Diluted vinegar only seemed marginally better than tap water for removing pesticide residues. Using full strength vinegar would get expensive, though. Thankfully there's something cheaper that works even better: salt water.

A 10% salt solution appears to work as good or better than full-strength vinegar. To make a 10% salt solution you just have to mix up about one-part salt to nine-parts water (though make sure to rinse all of the salt off before eating!).

There's not much you can do for the pesticides in animal products, though. The top sources of some pesticides are fruits and vegetables; but for other pesticides, it's dairy, eggs, and meat because the chemicals build up in fat. What do you do about pesticides in animal products? Hard boiling eggs appears to destroy more pesticides that scrambling, but for the pesticides that build up in the fat in fish or chicken, cooking can sometimes increase pesticide levels that obviously can't just wash off. In fact, washing meat, poultry, or eggs is considered one of the top ten dangerous food safety mistakes.

For more on organic foods, see:

The most important reason to wash produce is to reduce the risk of food-borne illness. Ironically, the food poisoning viruses may be found in the pesticides themselves. Check out my video Norovirus Food Poisoning from Pesticides.

In health,

Michael Greger, M.D.

PS: If you haven't yet, you can subscribe to my free videos here and watch my live, year-in-review presentations:

Image Credit: Sally Plank / Flickr. This image has been modified.

Original Link

The Best Way to Wash Fruit and Vegetables

The Best Way to Wash Fruit and Vegetables.jpeg

How might we reduce our exposure to pesticide residues on fruits and vegetables? What about staying away from imported produce? Well, it turns out domestic produce may be even worse, dispelling the notion that imported fruits and vegetables pose greater potential health risks to consumers.

Buying organic dramatically reduces dietary exposure to pesticides, but it does not eliminate the potential risk. Pesticide residues are detectable in about one in ten organic crop samples, due to cross-contamination from neighboring fields, the continued presence of very persistent pesticides like DDT in the soil, and accidental or fraudulent use.

By choosing organic, one hopes to shift exposures from a range of uncertain risk to more of a range of negligible risk, but even if all we had to eat were the most pesticide-laden of conventional produce, there is a clear consensus in the scientific community that the health benefits from consuming fruits and vegetables outweigh any potential risks from pesticide residues. And we can easily reduce whatever risk there is by rinsing our fruits and vegetables under running water.

There are, however, a plethora of products alleged by advertisers to reduce fruit and produce pesticide residues more effectively than water and touted to concerned consumers. For example, Procter & Gamble introduced a fruit and vegetable wash. As part of the introduction, T.G.I. Friday's jumped on board bragging on their menus that the cheese and bacon puddles they call potato skins were first washed with the new product. After all, it was proclaimed proven to be 98% more effective than water in removing pesticides.

So researchers put it to the test and it did no better than plain tap water.

Shortly thereafter Procter & Gamble discontinued the product, but numerous others took its place claiming their vegetable washes are three, four, five or even ten times more effective than water, to which a researcher replied, "That's mathematically impossible." If water removes 50%, you can't take off ten times more than 50%. They actually found water removed up to 80% of pesticide residues like the fungicide, Captan, for example. So, for veggie washes to brag they are three, four, five, ten times better than water is indeed mathematically questionable.

Other fruit and vegetable washes have since been put to the test. Researchers compared FIT Fruit & Vegetable Wash, Organiclean, Vegi-Clean, and dishwashing soap to just rinsing in plain tap water. 196 samples of lettuce, strawberries, and tomatoes were tested, and researchers found little or no difference between just rinsing with tap water compared to any of the veggie washes (or the dish soap). They all just seemed like a waste of money. The researchers concluded that just the mechanical action of rubbing the produce under tap water seemed to do it, and that using detergents or fruit and vegetable washes do not enhance the removal of pesticide residues from produce above that of just rinsing with tap water alone.

That may not be saying much, though. Captan appears to be the exception. When plain water was tried against a half dozen other pesticides, less than half the residues were removed.

Fingernail polish works better, but the goal is to end up with a less toxic, not a more toxic tomato.

We need a straightforward, plausible, and safe method for enhanced pesticide removal. Is there anything we can add to the water to boost its pesticide-stripping abilities? Check out my video, How to Make Your Own Fruit & Vegetable Wash.

If you soak potatoes in water, between about 2% to 13% of the pesticides are removed, but a 5% acetic acid solution removes up to 100%. What's that? Plain white vinegar. But 5% is full strength.

What about diluted vinegar? Diluted vinegar only seemed marginally better than tap water for removing pesticide residues. Using full strength vinegar would get expensive, though. Thankfully there's something cheaper that works even better: salt water.

A 10% salt solution appears to work as good or better than full-strength vinegar. To make a 10% salt solution you just have to mix up about one-part salt to nine-parts water (though make sure to rinse all of the salt off before eating!).

There's not much you can do for the pesticides in animal products, though. The top sources of some pesticides are fruits and vegetables; but for other pesticides, it's dairy, eggs, and meat because the chemicals build up in fat. What do you do about pesticides in animal products? Hard boiling eggs appears to destroy more pesticides that scrambling, but for the pesticides that build up in the fat in fish or chicken, cooking can sometimes increase pesticide levels that obviously can't just wash off. In fact, washing meat, poultry, or eggs is considered one of the top ten dangerous food safety mistakes.

For more on organic foods, see:

The most important reason to wash produce is to reduce the risk of food-borne illness. Ironically, the food poisoning viruses may be found in the pesticides themselves. Check out my video Norovirus Food Poisoning from Pesticides.

In health,

Michael Greger, M.D.

PS: If you haven't yet, you can subscribe to my free videos here and watch my live, year-in-review presentations:

Image Credit: Sally Plank / Flickr. This image has been modified.

Original Link

High Blood Pressure: Normal but Not Natural

High Blood Pressure - Normal but Not Natural.jpeg

The most comprehensive and systematic analysis of causes of death ever undertaken allows us to answer questions like, how many lives could we save if people cut back on soda? The answer is 299,521. Soft drinks aren't just bad because they're empty calories. More than just not being a health-promoting item, soda appears to be an actively death-promoting item. Of course, it's not as deadly as processed meats such as bacon, bologna, ham, or hot dogs, which account for about 800,000 deaths every year--killing twice as many women as domestic violence and five times more people than all illegal drugs combined.

On the other hand, eating more whole grains could save 1.7 million lives. And more vegetables could save 1.8 million lives every year. If only we ate more nuts and seeds, we'd save 2 and a half million lives. But fruit is apparently what the world needs most (they didn't look at beans) with 4.9 million lives hanging in the balance every year. The cure is not drugs or vaccines; the cure is fruit. The #1 dietary risk factor for death in the world may be not eating enough fruit.

One reason why plant-based diets can save so many millions is because the #1 killer risk factor in the world is high blood pressure, laying to waste nine million people year after year. In the United States, high blood pressure affects nearly 78 million--that's one in three of us. As we age our pressures get higher and higher, such that by age 60, it strikes more than half of that population. If it affects most of us when we get older, maybe it's less a disease and more just a natural, inevitable consequence of getting older?

No.

We've known for nearly a century that high blood pressure need never occur. Researchers measured the blood pressure of a thousand people in rural Kenya. Up until age 40, the blood pressures of rural Africans were about the same as Europeans and Americans, down around 120's over 80's, but as Westerners age, our pressures creep up such that by age 60 the average person is hypertensive, exceeding 140 over 90. But the pressures of those in rural Africa improved with age; not only did they not develop hypertension, their blood pressures actually got better.

The 140/90 cut-off is arbitrary. Just like studies that show the lower our cholesterol the better--there's really no safe level above about 150--blood pressure studies also support a "lower the better" approach. Even people who start out with blood pressure under 120/80 appear to benefit from blood pressure reduction. The ideal blood pressure, the no-benefit-from-reducing-it-further blood pressure, appears to be 110/70. Is it possible to get blood pressures under 110 over 70? It's not just possible, it can be normal for those eating healthy enough diets (see How Not to Die from High Blood Pressure).

Over two years at a rural Kenyan hospital, 1,800 patients were admitted. How many cases of high blood pressure were found? Zero. Wow. They must have had low rates of heart disease. Actually, they had no rates of heart disease. Not low risk--no risk. Not a single case of arteriosclerosis was found.

Having a "normal" blood pressure may set you up for dying from "normal" causes such as heart attacks and strokes. For more on this concept, see When Low Risk Means High Risk. It's like having a normal cholesterol level (see Optimal Cholesterol Level).

It seems high blood pressure is a choice. Like cavities: Cavities and Coronaries: Our Choice.

Even end-stage malignant hypertension can be reversed with diet (thereby demonstrating it was the diet and not other lifestyle factors that protected traditional plant-based populations). See Kempner Rice Diet: Whipping Us Into Shape.

Flax seeds, hibiscus tea, whole grains, and nitrate-rich vegetables may offer additional protection:

Why not just take the drugs? See The Actual Benefit of Diet vs. Drugs and Why Prevention is Worth a Ton of Cure. And be sure to check out my summary video, How Not to Die from High Blood Pressure, as well as The Evidence that Salt Raises Blood Pressure.

In health,

Michael Greger, M.D.

PS: If you haven't yet, you can subscribe to my free videos here and watch my live, year-in-review presentations:

Image Credit: Sally Plank / Flickr. This image has been modified.

Original Link

High Blood Pressure: Normal but Not Natural

High Blood Pressure - Normal but Not Natural.jpeg

The most comprehensive and systematic analysis of causes of death ever undertaken allows us to answer questions like, how many lives could we save if people cut back on soda? The answer is 299,521. Soft drinks aren't just bad because they're empty calories. More than just not being a health-promoting item, soda appears to be an actively death-promoting item. Of course, it's not as deadly as processed meats such as bacon, bologna, ham, or hot dogs, which account for about 800,000 deaths every year--killing twice as many women as domestic violence and five times more people than all illegal drugs combined.

On the other hand, eating more whole grains could save 1.7 million lives. And more vegetables could save 1.8 million lives every year. If only we ate more nuts and seeds, we'd save 2 and a half million lives. But fruit is apparently what the world needs most (they didn't look at beans) with 4.9 million lives hanging in the balance every year. The cure is not drugs or vaccines; the cure is fruit. The #1 dietary risk factor for death in the world may be not eating enough fruit.

One reason why plant-based diets can save so many millions is because the #1 killer risk factor in the world is high blood pressure, laying to waste nine million people year after year. In the United States, high blood pressure affects nearly 78 million--that's one in three of us. As we age our pressures get higher and higher, such that by age 60, it strikes more than half of that population. If it affects most of us when we get older, maybe it's less a disease and more just a natural, inevitable consequence of getting older?

No.

We've known for nearly a century that high blood pressure need never occur. Researchers measured the blood pressure of a thousand people in rural Kenya. Up until age 40, the blood pressures of rural Africans were about the same as Europeans and Americans, down around 120's over 80's, but as Westerners age, our pressures creep up such that by age 60 the average person is hypertensive, exceeding 140 over 90. But the pressures of those in rural Africa improved with age; not only did they not develop hypertension, their blood pressures actually got better.

The 140/90 cut-off is arbitrary. Just like studies that show the lower our cholesterol the better--there's really no safe level above about 150--blood pressure studies also support a "lower the better" approach. Even people who start out with blood pressure under 120/80 appear to benefit from blood pressure reduction. The ideal blood pressure, the no-benefit-from-reducing-it-further blood pressure, appears to be 110/70. Is it possible to get blood pressures under 110 over 70? It's not just possible, it can be normal for those eating healthy enough diets (see How Not to Die from High Blood Pressure).

Over two years at a rural Kenyan hospital, 1,800 patients were admitted. How many cases of high blood pressure were found? Zero. Wow. They must have had low rates of heart disease. Actually, they had no rates of heart disease. Not low risk--no risk. Not a single case of arteriosclerosis was found.

Having a "normal" blood pressure may set you up for dying from "normal" causes such as heart attacks and strokes. For more on this concept, see When Low Risk Means High Risk. It's like having a normal cholesterol level (see Optimal Cholesterol Level).

It seems high blood pressure is a choice. Like cavities: Cavities and Coronaries: Our Choice.

Even end-stage malignant hypertension can be reversed with diet (thereby demonstrating it was the diet and not other lifestyle factors that protected traditional plant-based populations). See Kempner Rice Diet: Whipping Us Into Shape.

Flax seeds, hibiscus tea, whole grains, and nitrate-rich vegetables may offer additional protection:

Why not just take the drugs? See The Actual Benefit of Diet vs. Drugs and Why Prevention is Worth a Ton of Cure. And be sure to check out my summary video, How Not to Die from High Blood Pressure, as well as The Evidence that Salt Raises Blood Pressure.

In health,

Michael Greger, M.D.

PS: If you haven't yet, you can subscribe to my free videos here and watch my live, year-in-review presentations:

Image Credit: Sally Plank / Flickr. This image has been modified.

Original Link

The Five Most Important Dietary Tweaks

The Five Most Important Dietary Tweaks.jpeg

Generally, adherence to healthy lifestyle patterns has decreased during the last 18 years. Obesity is up, exercise is down, and the number of people eating just five servings of fruits and veggies a day dropped like a rock. And we didn't start out that great to begin with.

Only 3% of Americans at the turn of the 21st century had the following four healthy lifestyle characteristics: not smoking, not overweight, five daily servings of fruits and vegetables, and exercising a half hour a day at least five days a week. Whether people were wealthy or college-educated didn't matter; no sub-group even remotely met clinical or public health recommendations.

Where are people falling down the most? You can see in my video What Percent of Americans Lead Healthy Lifestyles?. If you look at heart disease risk factors, for example, most people don't smoke and about half are exercising. But if we look at the healthy diet score-which is based on things like drinking less than four cups of soda a week-a scale of zero to five, only about 1% of Americans score a four or five. The American Heart Association's aggressive 2020 target to improve that by 20% would bring us up to 1.2%.

Since we've known for decades that advanced coronary artery disease may be present by age 20--with atherosclerosis often even present in young children--it is particularly disturbing that healthy lifestyle choices are declining rather than improving in the U.S.

In terms of life expectancy, the U.S. is down around 27 or 28 out of the 34 OECD free-market democracies. The people of Slovenia live a year longer than citizens of the United States. Why? According to the most rigorous analysis of risk factors ever published, the number one cause of death and disability in the United States is our diet.

It's the food.

According to the Global Burden of Disease study, the worst five things about our diet are: we don't eat enough fruit, we don't eat enough nuts and seeds, we eat too much salt, too much processed meat, and not enough vegetables.

Studies that have looked at diet quality and chronic disease mortality risk found that those scoring higher (e.g. more whole plant foods), reduced the risk of dying prematurely from heart disease, cancer, and all causes of death combined. There is now an overwhelming body of clinical and epidemiological evidence illustrating the dramatic impact of a healthy lifestyle on reducing all-cause mortality and preventing chronic diseases such as coronary heart disease, stroke, diabetes, and cancer.

Why do we eat so poorly? Aren't we scared of dying from these horrible chronic diseases? It's almost as if we're eating as though our future didn't matter. And there's actually data to back that up, from a study entitled Death Row Nutrition.

The growing macabre fascination with speculating about one's ''last meal'' offers a window into one's true consumption desires when one's value of the future is discounted close to zero. In contrast to pop culture anecdotes, a group of Cornell researchers created a catalog of actual last meals-the final food requests of 247 individuals executed in the United States during a recent five-year period. Meat was the most common request. The researchers go out of their way to note that tofu never made the list, and no one asked for a vegetarian meal. In fact, if you compare the last meals to what Americans normally eat, there's not much difference.

If we continue to eat as though they were our last meals, eventually, they will be.


A few years ago I did a video called Nation's Diet in Crisis. It's sad that it doesn't seem like much has changed. How Many Meet the Simple Seven? is another video in which you can see how your own habits stack up.

For more on fruits and veggies and living longer, see Fruits and Longevity: How Many Minutes per Mouthful? Surprised that nuts made the longevity list? See Nuts May Help Prevent Death. What about legumes? See Increased Lifespan from Beans.

The reason public health professionals are so keen on measuring lifestyle characteristics is because modest improvements may have extraordinary effects. See, for example:

Didn't know the beginnings of heart disease may already be present in children? See my video Heart Disease Starts in Childhood. Think that's tragic? Check out Heart Disease May Start in the Womb. Is it too late if we've been eating poorly most of our lives? It's Never Too Late to Start Eating Healthier.

In health,

Michael Greger, M.D.

PS: If you haven't yet, you can subscribe to my free videos here and watch my live, year-in-review presentations:

Image Credit: Sally Plank / Flickr. This image has been modified.

Original Link

The Five Most Important Dietary Tweaks

The Five Most Important Dietary Tweaks.jpeg

Generally, adherence to healthy lifestyle patterns has decreased during the last 18 years. Obesity is up, exercise is down, and the number of people eating just five servings of fruits and veggies a day dropped like a rock. And we didn't start out that great to begin with.

Only 3% of Americans at the turn of the 21st century had the following four healthy lifestyle characteristics: not smoking, not overweight, five daily servings of fruits and vegetables, and exercising a half hour a day at least five days a week. Whether people were wealthy or college-educated didn't matter; no sub-group even remotely met clinical or public health recommendations.

Where are people falling down the most? You can see in my video What Percent of Americans Lead Healthy Lifestyles?. If you look at heart disease risk factors, for example, most people don't smoke and about half are exercising. But if we look at the healthy diet score-which is based on things like drinking less than four cups of soda a week-a scale of zero to five, only about 1% of Americans score a four or five. The American Heart Association's aggressive 2020 target to improve that by 20% would bring us up to 1.2%.

Since we've known for decades that advanced coronary artery disease may be present by age 20--with atherosclerosis often even present in young children--it is particularly disturbing that healthy lifestyle choices are declining rather than improving in the U.S.

In terms of life expectancy, the U.S. is down around 27 or 28 out of the 34 OECD free-market democracies. The people of Slovenia live a year longer than citizens of the United States. Why? According to the most rigorous analysis of risk factors ever published, the number one cause of death and disability in the United States is our diet.

It's the food.

According to the Global Burden of Disease study, the worst five things about our diet are: we don't eat enough fruit, we don't eat enough nuts and seeds, we eat too much salt, too much processed meat, and not enough vegetables.

Studies that have looked at diet quality and chronic disease mortality risk found that those scoring higher (e.g. more whole plant foods), reduced the risk of dying prematurely from heart disease, cancer, and all causes of death combined. There is now an overwhelming body of clinical and epidemiological evidence illustrating the dramatic impact of a healthy lifestyle on reducing all-cause mortality and preventing chronic diseases such as coronary heart disease, stroke, diabetes, and cancer.

Why do we eat so poorly? Aren't we scared of dying from these horrible chronic diseases? It's almost as if we're eating as though our future didn't matter. And there's actually data to back that up, from a study entitled Death Row Nutrition.

The growing macabre fascination with speculating about one's ''last meal'' offers a window into one's true consumption desires when one's value of the future is discounted close to zero. In contrast to pop culture anecdotes, a group of Cornell researchers created a catalog of actual last meals-the final food requests of 247 individuals executed in the United States during a recent five-year period. Meat was the most common request. The researchers go out of their way to note that tofu never made the list, and no one asked for a vegetarian meal. In fact, if you compare the last meals to what Americans normally eat, there's not much difference.

If we continue to eat as though they were our last meals, eventually, they will be.


A few years ago I did a video called Nation's Diet in Crisis. It's sad that it doesn't seem like much has changed. How Many Meet the Simple Seven? is another video in which you can see how your own habits stack up.

For more on fruits and veggies and living longer, see Fruits and Longevity: How Many Minutes per Mouthful? Surprised that nuts made the longevity list? See Nuts May Help Prevent Death. What about legumes? See Increased Lifespan from Beans.

The reason public health professionals are so keen on measuring lifestyle characteristics is because modest improvements may have extraordinary effects. See, for example:

Didn't know the beginnings of heart disease may already be present in children? See my video Heart Disease Starts in Childhood. Think that's tragic? Check out Heart Disease May Start in the Womb. Is it too late if we've been eating poorly most of our lives? It's Never Too Late to Start Eating Healthier.

In health,

Michael Greger, M.D.

PS: If you haven't yet, you can subscribe to my free videos here and watch my live, year-in-review presentations:

Image Credit: Sally Plank / Flickr. This image has been modified.

Original Link

How a Low-Carb Diet is Metabolically Like Being Obese

NF-Nov22 The Spillover Effect copy.jpg

Free fatty acids (meaning fat circulating in the bloodstream not packaged into triglycerides) result in inflammation, toxic fat breakdown products, and oxidative stress, which can gum up the insulin receptor pathway and lead to insulin resistance in our muscles. Insulin resistance is what causes prediabetes and type 2 diabetes. I explain the process in my video What Causes Insulin Resistance? As the level of fat in the blood rises, the body's ability to clear sugar from the blood drops dramatically.

Where does this fat in our blood that's wreaking all this havoc come from? It comes from the fat that we eat and from the fat that we wear.

The number of fat cells we have stays constant in adulthood. The way researchers figured that out is by measuring the amount of radioactive carbon still trapped in our DNA from all the nuclear bomb tests. After massive weight loss, our fat cells shrink as they offload fat, but the number stays the same. Conversely, when we gain weight, our fat cells stretch as we pack more and more into each individual fat cell. So, when our belly, butt, or thighs get big, we're not adding more fat cells, we're just cramming more fat into each cell. At a certain point, our cells become so bloated that they spill fat back into the bloodstream.

This is called the spillover effect. Not only does an obese person have more fat, but they're constantly spilling that fat into their bloodstream. So that could be the link between obesity and diabetes. Fat is spilling out from our fat cells and gets lodged in our muscle cells, leading to the insulin resistance that promotes the onset of type 2 diabetes. I show this in my video The Spillover Effect Links Obesity to Diabetes.

The fat can also enter our bloodstream through our mouth. If you put people on a low carb diet, fat builds up in their muscle within two hours and insulin sensitivity drops. And the more fat found in the muscle, the lower the ability to clear sugar from the blood. It doesn't take years for this to happen, just hours after fatty foods go into our mouths. A fat-rich diet can increase fat in the blood and this increase is accompanied by a decrease in insulin sensitivity.

Studies clearly demonstrate that fat in the blood directly inhibit glucose transport and usage in our muscles, which is responsible for clearing about 85% of the glucose out of blood. These findings indicate that fat consumption can play an important role in the development of insulin resistance.

Normally we only have 10 to 50 micromoles of free fat floating around in our blood stream at any one time, but those who are obese have between 60 to 80. But, we can reach 80 just eating a high fat diet. So a skinny person eating a low-carb diet can have the same level of fat in their blood that obese people do. Similarly, being obese is like eating some horrible bacon and butter diet all day, because obese persons are constantly spilling fat into their bloodstream, no matter what goes in their mouth.

Are all types of fat the same? Find out the answer in my video Lipotoxicity: How Saturated Fat Raises Blood Sugar.

The fat leaking into our bloodstream may also contain fat-soluble pollutants that accumulated from our diet: Pollutants in Salmon and Our Own Fat.

The spillover effect may also help explain the increased heart disease risk associated with obesity: Low Carb Diets and Coronary Blood Flow.

In health,

Michael Greger, M.D.

PS: If you haven't yet, you can subscribe to my free videos here and watch my live, year-in-review presentations:

Image Credit: [Eugene Bochkarev] © 123RF.com

Original Link

How a Low-Carb Diet is Metabolically Like Being Obese

NF-Nov22 The Spillover Effect copy.jpg

Free fatty acids (meaning fat circulating in the bloodstream not packaged into triglycerides) result in inflammation, toxic fat breakdown products, and oxidative stress, which can gum up the insulin receptor pathway and lead to insulin resistance in our muscles. Insulin resistance is what causes prediabetes and type 2 diabetes. I explain the process in my video What Causes Insulin Resistance? As the level of fat in the blood rises, the body's ability to clear sugar from the blood drops dramatically.

Where does this fat in our blood that's wreaking all this havoc come from? It comes from the fat that we eat and from the fat that we wear.

The number of fat cells we have stays constant in adulthood. The way researchers figured that out is by measuring the amount of radioactive carbon still trapped in our DNA from all the nuclear bomb tests. After massive weight loss, our fat cells shrink as they offload fat, but the number stays the same. Conversely, when we gain weight, our fat cells stretch as we pack more and more into each individual fat cell. So, when our belly, butt, or thighs get big, we're not adding more fat cells, we're just cramming more fat into each cell. At a certain point, our cells become so bloated that they spill fat back into the bloodstream.

This is called the spillover effect. Not only does an obese person have more fat, but they're constantly spilling that fat into their bloodstream. So that could be the link between obesity and diabetes. Fat is spilling out from our fat cells and gets lodged in our muscle cells, leading to the insulin resistance that promotes the onset of type 2 diabetes. I show this in my video The Spillover Effect Links Obesity to Diabetes.

The fat can also enter our bloodstream through our mouth. If you put people on a low carb diet, fat builds up in their muscle within two hours and insulin sensitivity drops. And the more fat found in the muscle, the lower the ability to clear sugar from the blood. It doesn't take years for this to happen, just hours after fatty foods go into our mouths. A fat-rich diet can increase fat in the blood and this increase is accompanied by a decrease in insulin sensitivity.

Studies clearly demonstrate that fat in the blood directly inhibit glucose transport and usage in our muscles, which is responsible for clearing about 85% of the glucose out of blood. These findings indicate that fat consumption can play an important role in the development of insulin resistance.

Normally we only have 10 to 50 micromoles of free fat floating around in our blood stream at any one time, but those who are obese have between 60 to 80. But, we can reach 80 just eating a high fat diet. So a skinny person eating a low-carb diet can have the same level of fat in their blood that obese people do. Similarly, being obese is like eating some horrible bacon and butter diet all day, because obese persons are constantly spilling fat into their bloodstream, no matter what goes in their mouth.

Are all types of fat the same? Find out the answer in my video Lipotoxicity: How Saturated Fat Raises Blood Sugar.

The fat leaking into our bloodstream may also contain fat-soluble pollutants that accumulated from our diet: Pollutants in Salmon and Our Own Fat.

The spillover effect may also help explain the increased heart disease risk associated with obesity: Low Carb Diets and Coronary Blood Flow.

In health,

Michael Greger, M.D.

PS: If you haven't yet, you can subscribe to my free videos here and watch my live, year-in-review presentations:

Image Credit: [Eugene Bochkarev] © 123RF.com

Original Link

The Natural Human Diet

NF-Nov15 The Problem with the Paleo Diet Argument copy.jpg

Our epidemics of dietary disease have prompted a great deal of research into what humans are meant to eat for optimal health. In 1985, an influential article highlighted in my video The Problem With the Paleo Diet Argument was published proposing that our chronic diseases stem from a disconnect between what our bodies ate while evolving during the Stone Age (about 2 million years ago) and what we're stuffing our face with today. The proposal advocated for a return towards a hunter-gatherer type diet of lean meat, fruits, vegetables, and nuts.

It's reasonable to assume our nutritional requirements were established in the prehistoric past. However, the question of which prehistoric past we should emulate remains. Why just the last 2 million? We've been evolving for about 20 million years since our last common great ape ancestor, during which our nutrient requirements and digestive physiology were set down. Therefore our hunter-gatherer days at the tail end probably had little effect. What were we eating for the first 90% of our evolution? What the rest of the great apes ended up eating--95 percent or more plants.

This may explain why we're so susceptible to heart disease. For most of human evolution, cholesterol may have been virtually absent from the diet. No bacon, butter, or trans fats; and massive amounts of fiber, which pulls cholesterol from the body. This could have been a problem since our body needs a certain amount of cholesterol, but our bodies evolve not only to make cholesterol, but also to preserve it and recycle it.

If we think of the human body as a cholesterol-conserving machine, then plop it into the modern world of bacon, eggs, cheese, chicken, pork, and pastry; it's no wonder artery-clogging heart disease is our #1 cause of death. What used to be adaptive for 90% of our evolution--holding on to cholesterol at all costs since we weren't getting much in our diet--is today maladaptive, a liability leading to the clogging of our arteries. Our bodies just can't handle it.

As the editor-in-chief of the American Journal of Cardiology noted 25 years ago, no matter how much fat and cholesterol carnivores eat, they do not develop atherosclerosis. We can feed a dog 500 eggs worth of cholesterol and they just wag their tail; a dog's body is used to eating and getting rid of excess cholesterol. Conversely, within months a fraction of that cholesterol can start clogging the arteries of animals adapted to eating a more plant-based diet.

Even if our bodies were designed by natural selection to eat mostly fruit, greens and seeds for 90% of our evolution, why didn't we better adapt to meat-eating in the last 10%, during the Paleolithic? We've had nearly 2 million years to get used to all that extra saturated fat and cholesterol. If a lifetime of eating like that clogs up nearly everyone's arteries, why didn't the genes of those who got heart attacks die off and get replaced by those that could live to a ripe old age with clean arteries regardless of what they ate? Because most didn't survive into old age.

Most prehistoric peoples didn't live long enough to get heart attacks. When the average life expectancy is 25 years old, then the genes that get passed along are those that can live to reproductive age by any means necessary, and that means not dying of starvation. The more calories in food, the better. Eating lots of bone marrow and brains, human or otherwise, would have a selective advantage (as would discovering a time machine stash of Twinkies for that matter!). If we only have to live long enough to get our kids to puberty to pass along our genes, then we don't have to evolve any protections against the ravages of chronic disease.

To find a population nearly free of chronic disease in old age, we don't have to go back a million years. In the 20th century, networks of missionary hospitals in rural Africa found coronary artery disease virtually absent, and not just heart disease, but high blood pressure, stroke, diabetes, common cancers, and more. In a sense, these populations in rural China and Africa were eating the type of diet we've been eating for 90% of the last 20 million years, a diet almost exclusively of plant foods.

How do we know it was their diet and not something else? In the 25 year update to their original paleo paper, the authors tried to clarify that they did not then and do not now propose that people adopt a particular diet just based on what our ancient ancestors ate. Dietary recommendations must be put to the test. That's why the pioneering research from Pritikin, Ornish, and Esselstyn is so important, showing that plant-based diets can not only stop heart disease but have been proven to reverse it in the majority of patients. Indeed, it's the only diet that ever has.

For more on the absence of Western diseases in plant-based rural populations, see for example:

I've touched on "paleo" diets in the past:

In health,

Michael Greger, M.D.

PS: If you haven't yet, you can subscribe to my free videos here and watch my live, year-in-review presentations:

Image Credit: Nathan Rupert / Flickr

Original Link

The Natural Human Diet

NF-Nov15 The Problem with the Paleo Diet Argument copy.jpg

Our epidemics of dietary disease have prompted a great deal of research into what humans are meant to eat for optimal health. In 1985, an influential article highlighted in my video The Problem With the Paleo Diet Argument was published proposing that our chronic diseases stem from a disconnect between what our bodies ate while evolving during the Stone Age (about 2 million years ago) and what we're stuffing our face with today. The proposal advocated for a return towards a hunter-gatherer type diet of lean meat, fruits, vegetables, and nuts.

It's reasonable to assume our nutritional requirements were established in the prehistoric past. However, the question of which prehistoric past we should emulate remains. Why just the last 2 million? We've been evolving for about 20 million years since our last common great ape ancestor, during which our nutrient requirements and digestive physiology were set down. Therefore our hunter-gatherer days at the tail end probably had little effect. What were we eating for the first 90% of our evolution? What the rest of the great apes ended up eating--95 percent or more plants.

This may explain why we're so susceptible to heart disease. For most of human evolution, cholesterol may have been virtually absent from the diet. No bacon, butter, or trans fats; and massive amounts of fiber, which pulls cholesterol from the body. This could have been a problem since our body needs a certain amount of cholesterol, but our bodies evolve not only to make cholesterol, but also to preserve it and recycle it.

If we think of the human body as a cholesterol-conserving machine, then plop it into the modern world of bacon, eggs, cheese, chicken, pork, and pastry; it's no wonder artery-clogging heart disease is our #1 cause of death. What used to be adaptive for 90% of our evolution--holding on to cholesterol at all costs since we weren't getting much in our diet--is today maladaptive, a liability leading to the clogging of our arteries. Our bodies just can't handle it.

As the editor-in-chief of the American Journal of Cardiology noted 25 years ago, no matter how much fat and cholesterol carnivores eat, they do not develop atherosclerosis. We can feed a dog 500 eggs worth of cholesterol and they just wag their tail; a dog's body is used to eating and getting rid of excess cholesterol. Conversely, within months a fraction of that cholesterol can start clogging the arteries of animals adapted to eating a more plant-based diet.

Even if our bodies were designed by natural selection to eat mostly fruit, greens and seeds for 90% of our evolution, why didn't we better adapt to meat-eating in the last 10%, during the Paleolithic? We've had nearly 2 million years to get used to all that extra saturated fat and cholesterol. If a lifetime of eating like that clogs up nearly everyone's arteries, why didn't the genes of those who got heart attacks die off and get replaced by those that could live to a ripe old age with clean arteries regardless of what they ate? Because most didn't survive into old age.

Most prehistoric peoples didn't live long enough to get heart attacks. When the average life expectancy is 25 years old, then the genes that get passed along are those that can live to reproductive age by any means necessary, and that means not dying of starvation. The more calories in food, the better. Eating lots of bone marrow and brains, human or otherwise, would have a selective advantage (as would discovering a time machine stash of Twinkies for that matter!). If we only have to live long enough to get our kids to puberty to pass along our genes, then we don't have to evolve any protections against the ravages of chronic disease.

To find a population nearly free of chronic disease in old age, we don't have to go back a million years. In the 20th century, networks of missionary hospitals in rural Africa found coronary artery disease virtually absent, and not just heart disease, but high blood pressure, stroke, diabetes, common cancers, and more. In a sense, these populations in rural China and Africa were eating the type of diet we've been eating for 90% of the last 20 million years, a diet almost exclusively of plant foods.

How do we know it was their diet and not something else? In the 25 year update to their original paleo paper, the authors tried to clarify that they did not then and do not now propose that people adopt a particular diet just based on what our ancient ancestors ate. Dietary recommendations must be put to the test. That's why the pioneering research from Pritikin, Ornish, and Esselstyn is so important, showing that plant-based diets can not only stop heart disease but have been proven to reverse it in the majority of patients. Indeed, it's the only diet that ever has.

For more on the absence of Western diseases in plant-based rural populations, see for example:

I've touched on "paleo" diets in the past:

In health,

Michael Greger, M.D.

PS: If you haven't yet, you can subscribe to my free videos here and watch my live, year-in-review presentations:

Image Credit: Nathan Rupert / Flickr

Original Link